Ringworm in Cats and Dogs

In animals, ringworm usually appears as a crusty or scaly patch on the skin with some hair loss. The affected areas may become red or irritated looking. Ringworm is sometimes itchy.

Occasionally, ringworm will fluoresce under a black light.

Unfortunately, a cat can have ringworm and not show any skin lesions at all.

A fungal culture is the best test to diagnose ringworm; it typically takes one to three weeks to get results. Fungal cultures will also be used to monitor the progress of treatment.

Call your veterinarian if you notice any hair loss or excessive itching in your dog or cat.

What is Ringworm?

Ringworm is not actually caused by a worm, but rather by a fungus that infects the outer layer of skin and hair. It is a zoonotic disease, meaning it can be transmitted from pets to humans, or people to pets. There are numerous species of ringworm. It is most commonly recognized in cats (often kittens) and dogs, although rabbits and rodents can also become infected. Ringworm can be very contagious.

Can I Get Ringworm from My Pet?

Yes. Anyone that has come into contact with the infected animal or its environment has the chance of contracting ringworm. In people, the infection may appear on the skin as a ring with reddish borders and is usually itchy. If you have any concerns about ringworm in family members, please seek advice from your physician.

How is Ringworm Treated?

Ringworm is easily treatable in humans with only topical medication. However, this is not the case with pets. In order to eliminate ringworm from animals, topical and oral anti-fungal medications are required, and it often takes months for complete resolution. Oral medication is either itraconazole or fluconazole. Topical medications are daily miconazole or clotrimazole creams plus weekly lime sulfur dips. Once the skin starts to improve, a fungal culture will be obtained and sent out to monitor the status. As soon as there is one negative culture, a second culture will be sent to the lab. Dermatologists recommend that treatment be continued for one month beyond the second negative culture. It is important that your pet receive their medication and treatment regularly.

How Do I Clean My House?

Ringworm spores can survive in the environment for two years. Pets and people can become re-infected if the house isn’t properly cleaned.

The best product to kill ringworm is bleach (1:10 dilution with hot water). You can also use Lysol with Bleach or 409. Make sure to use any product liberally and repeat cleaning daily.

Vacuum carpets, floors, and furniture frequently and dispose of the vacuum bag immediately.

All curtains, comforters, etc. should be dry cleaned at a professional cleaner.

Clean all air vents and change filters often.

It is also recommended that items that cannot be bleached (e.g. floor rug, couch, etc.) be placed outside in the sun on a hot day.

During office hours call us immediately at 781-596-0510 and we'll ensure that your pet receives our medical care as quickly as is necessary.

Nearby clinics that provide after hours emergency care:

Massachusetts Veterinary Referral Hospital provides 24-hour emergency and critical care services for companion animals as well as for sick or injured wildlife. They are located at 20 Cabot Rd, Woburn, MA 01801. Phone (781)932-5802

Angel Memorial Medical Center, Boston provides 24-hour emergency and critical care services for companion animals as well as for sick or injured wildlife. They are located at 350 South Huntington Ave, Boston MA . Phone (617)522-7282